<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>v-bind高级</title>
    <style>
        .select {
            height: 100px;
            width: 700px;
        }
    </style>
</head>
<body>
<div id="app">
    <!--此时class的值只能是haha，但是具体是不是要看flag，
    如果flag为true，则class的值就是哈哈，否则就为“”-->
    <div @mouseover="info=1" style="border: 1px red solid" v-bind:class="{select:info==1}">1</div>
    <div @mouseover="info=2" style="border: 1px red solid" v-bind:class="{select:info==2}">2</div>
    <div @mouseover="info=3" style="border: 1px red solid" v-bind:class="{select:info==3}">3</div>
</div>
<script src="../node_modules/vue/dist/vue.js"></script>
<script>
    let vue = new Vue({
            el: "#app",
            data: {
                info: 1
            }
        })
    ;
</script>
</body>
</html>